The incidence of breast cancer varies depending on a woman's age. The National Cancer Institute gives the following probabilities for a randomly chosen woman in her 40s who takes a mammography to screen for breast cancer:

What percent of women in their 40s taking a screening mammography receive a positive test result?

97%

13.96%

11.68%

2.28%

If a randomly chosen woman in her 40s taking the mammography screening test gets a positive test result, the probability that she indeed has breast cancer is the positive predicted value, PPV = P(Cancer | Positive test). The PPV for this age group is

0.8368.

0.1632.

0.85.

0.0268.
 

0.8 Positive Cancer 0.0286 Negative 0.2 Mammography 0,1 Positive 0.9714 No cancer Negativel 0.9